title: Cervical spine injury biomechanics: Applications for under body blast loadings in military environments.
abstract: BACKGROUND
  While cervical spine injury biomechanics reviews in motor vehicle and sports environments are available, there is a paucity of studies in military loadings. This article presents an analysis on the biomechanics and applications of cervical spine injury research with an emphasis on human tolerance for underbody blast loadings in the military.
  
  
  METHODS
  Following a brief review of published military studies on the occurrence and identification of field trauma, postmortem human subject investigations are described using whole body, intact head-neck complex, osteo-ligamentous cervical spine with head, subaxial cervical column, and isolated segments subjected to differing types of dynamic loadings (electrohydraulic and pendulum impact devices, free-fall drops).
  
  
  RESULTS
  Spine injuries have shown an increasing trend over the years, explosive devices are one of the primary causal agents and trauma is attributed to vertical loads. Injuries, mechanisms and tolerances are discussed under these loads. Probability-based injury risk curves are included based on loading rate, direction and age.
  
  
  CONCLUSIONS
  A unique advantage of human cadaver tests is the ability to obtain fundamental data to delineate injury biomechanics and establish human tolerance and injury criteria. Definitions of tolerances of the spine under vertical loads based on injuries have implications in clinical and biomechanical applications. Primary outputs such as forces and moments can be used to derive secondary variables such as the neck injury criterion. Implications are discussed for designing anthropomorphic test devices that may be used to predict injuries in underbody blast environments and improve the safety of military personnel.
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226, USA. yoga@mcw.edu
authors.forename: Narayan
authors.initials: N
authors.lastname: Yoganandan
authors.forename: Brian D
authors.initials: BD
authors.lastname: Stemper
authors.forename: Frank A
authors.initials: FA
authors.lastname: Pintar
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Maiman
authors.forename: B Joseph
authors.initials: BJ
authors.lastname: McEntire
authors.forename: Valeta Carol
authors.initials: VC
authors.lastname: Chancey
mesh_terms: D001696:Biomechanical Phenomena; D001753:Blast Injuries / Q000453:epidemiology / Q000503:physiopathology* / Q000517:prevention & control; D002102:Cadaver; D002574:Cervical Vertebrae / Q000293:injuries* / Q000503:physiopathology*; D006801:Humans; D015994:Incidence; D008348:Manikins; D008889:Military Personnel; D008953:Models, Anatomic; D019838:Neck Injuries / Q000453:epidemiology / Q000503:physiopathology* / Q000517:prevention & control; D011187:Posture / Q000502:physiology; D016103:Spinal Fractures / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control; D013124:Spinal Injuries / Q000453:epidemiology / Q000503:physiopathology* / Q000517:prevention & control; D014481:United States / Q000453:epidemiology; D016474:Weight-Bearing / Q000502:physiology
keywords: Experimental studies; Fracture tolerance; Human cervical spine; Injury risk curves; Military environments; Underbody blast loadings